The use of solid-state electronics to replace electromechanical mechanisms in low-power consumer electronics has resulted in tremendous improvements in product performance, capability, and reliability. This can be attributed to rapid and novel advances in the semiconductor device and electronic packaging industries. Developments in high-power electronics packaging, driven by the military and industrial sectors emphasizing the transportation (e.g., next-generation shipboard systems and electric/electric-hybrid vehicles), aerospace (e.g., next-generation “fly-by-light, power-by-wire” jetliners), telecommunication (e.g., satellite power systems), and electric utility markets (e.g., inverter-based flexible AC transmission system controllers), is considered to be in an early stage of industry development. The main impetus for this effort is to enable development of common modular and integrated designs scalable to numerous applications which are constrained by reliability, mass, footprint, volume, manufacturing and cost considerations.
Heat management in power discrete semiconductor packages, in particular for DC-DC or DC-AC converters, has seen slow progress in terms of improved heat management. These converters often employ multiple parallel SO-8 devices, such as synchronous rectifiers, due to printed circuit board (PCB) real estate constraints. The layout of the PCB becomes congested due to the parallel arrangement of the original legacy power packages. Traditionally in SOIC leaded form, an SO-8 package is thermally inferior in handling high current and high power devices. Typically, the junction-to-solder point thermal resistance of an SO-8 device is in the range of 20 k/W to 30 k/W, depending on the chip size and current rating. This means the inferior thermal capability of the SO-8 package has necessitated the need to parallel multiple devices in order to spread the power dissipation and prevent any one device from running too hot. Unfortunately, too many devices in parallel, by occupying the PCB real estate, may also lead to excessive source-to-drain current discharges in the connecting MOSFET drivers, as well as having negative impact on the converter's overall efficiency.
Thus, a need still remains for a system of thermally enhanced stackable semiconductor packages. In view of the demand to shrink device form factors on PCB's and increase the power dissipation capabilities, it is increasingly critical that answers be found to these problems. In view of the ever-increasing need to save costs and improve efficiencies, it is more and more critical that answers be found to these problems.
Solutions to these problems have been long sought but prior developments have not taught or suggested any solutions and, thus, solutions to these problems have long eluded those skilled in the art.